w(Fe)/w(Ni)对Mo2FeB2基金属陶瓷的影响.

Mo2FeB2 based cermets with different w（Fe）/w（Ni）（10∶0, 7∶3, 5∶5, 3∶7） were prepared by the vacuum liquid phase sintering with MoB, Fe, Ni, and Cr powders as raw materials. The effects of w（Fe）/w（Ni） on the phase compositions, microstructures and mechanical properties of cermets were investigated. The results showed that the compositions of hard and binder phases of boride-based cermet with different w（Fe）/w（Ni） were different. When w（Fe）/w（Ni） of 3∶7, the hard phase was composed of Mo2NiB2 and Mo2FeB2; while in the cases of other w（Fe）/w（Ni）, the hard phase was Mo2FeB2. At 1 350 ℃, the microstructure of cermets was uniform and the size of pore is minimized, with the increase of sintering temperature, the hard-phase particles aggregated and the microstructure was not homogeneous, which led to the decrease of mechanical properties. After sintering at 1350 ℃ for 2 h, the hardness and bending strength of the obtained cermet（w（Fe）/w（Ni）=10∶0） reached the maximum, which were 82.1 HRA and 1 498.7 MPa respectively. Meanwhile, the analysis of fracture morphology revealed that a large number of dimples and rich tearing edges are closely related to the improvement of the bending strength of cermets. [ABSTRACT FROM AUTHOR]